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RE: Oops...time to change that tube

Posted by immatthewj on June 27, 2023 at 20:12:34

In Reply to: Oops...time to change that tube posted by Byrd69 on June 25, 2023 at 16:25:19:

This will fall into the TMI category:

1) in my first tube amp (Cary SLA 70) a set of 4 Svetlanta 6550Bs (original with amp) in the mid 90s due to the bass turning crappy & the trebles getting edgy

2) in the same amp a pair of 6SL7s because the amp was starting to sound crappy again, this was later on in the 90s

3) over the course of owning that amp I've replaced at least 3 rectifier tubes because they were flashing or arcing on start up or actually quit working (but they were all Sovtecs)

4) in '99 I picked up a 2cond hand SLP90 that actually had a nonfunctional Telefunken 12au7 in it (must have been one of Andy's--they all had red/green nail polish on top of them) when I took it home from the dealer to audition

5) same preamp: the system went into storage for 10 years or so & when I brought it out in Fall of '17 it sounded good but after a while it started popping & crackling & I troubleshot it down to one of the 6 replacement 12au7s I bought from Andy, so I bought a pair of Phillips 12au7s from Cary & one of them went microphonic after a short period of time

6) in (I think it was) '97 or '98 I bought a pair of second hand ARC VTM120s & I lost count of how many 6550s that those amps took down (or as ARC claimed, were taking down the amp)

7) in spring of '01 I replaced those ARCs with a new Cary V-12 and within a few monthes (I seem to remember it was prior to 9/11) one of the Ruby EL34s went south

8) the Cary V12 was part of the system that came out of storage in '17 & when I put it back into service I bought a dozen reissued Mullard EL34s from Viva (however this was not failure related, I just felt that the original Rubys were sounding tired) and Viva's Russian Mullatrds did not last long at all. Bias was doing weird things on one side--however, this tube anomaly may have been due to some operator malfeasances/errors. I replaced them (in the spring of '20, I think) with a dozen reissued Tungsols from Jim McShane and they have held up absolutely excellently

9) I think it was about two years ago that I bought a preowned SLP-05 from Cary, and I got the deal of a lifetime on several pairs of vintage SN7s/VT231s and I completely fell in love with a pair of RCA black glass VT231s in the balanced input sockets (while running the EHs that Cary provided in the other 4 sockets) and I liked those RCAs so much that one night when I was drinking & surfing ebay I found some guy from France selling a sextet of RCA blackglass VT231s that I thought, "wouldn't 6 of those tubes sound great!" so I bought them & not long after I had them in, I lost a channel, and sure enough, two of those tubes from France were cold, so I moved some tubes around and had 4 of the tubes from France in the phase splitter sockets with that first pair I alluded to in the balanced sockets, and . . . you guessed it . . . after a while I lost a channel and two more of those tubes from France were cold . . . so I put the remaining two operational tubes from France in storage, went back to configuring the preamp with the first pair of RCA VT231s in the balanced sockets and the EHs Cary sent it out with in the 4 phase splitter sockets.

Edits: 06/27/23 06/27/23 06/27/23 06/27/23 06/27/23 06/28/23

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